HOMOGENEOUS and HETEROGENEOUS are antonyms. HOMOGENEOUS describes things that are all of the same kind. In contrast, HETEROGENEOUS describes things that are diverse in character or content. Although the definitions of these two words are relatively easy, SAT test writers have crafted difficult vocabulary in context questions that place HOMOGENEOUS and HETEROGENEOUS in unexpected contexts. For example, recent questions asked students to consider the distribution of horse populations across Eurasia and the clustering of cutlery manufacturing firms in Sheffield, England. The highly mobile DOM2 breed of horses has supplanted or replaced other horse breeds and is thus a HOMOGENEOUS presence across Eurasia. Meanwhile, in England, a HETEROGENEOUS or variable mix of different factors drives firms to locate and thus cluster in the same area.